X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?p=ez.git;a=blobdiff_plain;f=ez.el;h=e899ab46493c68f693418ce9e0baa0331796fb6f;hp=4cea0751162b39b6cbb55bfbdf5d7f5e6f182d97;hb=9d1263da3e1499040fe258ea8dea1c60ae7ccf6a;hpb=9ac00a55f5cf3053b2224fb6d1a6189905e51587

diff --git a/ez.el b/ez.el
index 4cea075..e899ab4 100644
--- a/ez.el
+++ b/ez.el
@@ -28,7 +28,27 @@
 
 ;;; Code:
 
-;; Character set tables
+;; Utility functions
+
+(defun ez-decode-signed-bits (n nbits)
+  (if (= 0 (lsh n (- 1 nbits)))
+      n
+    (- n (lsh 1 nbits))))
+
+(defun ez-decode-signed-byte (b)
+  (ez-decode-signed-bits b 8))
+
+(defun ez-decode-signed-word (w)
+  (ez-decode-signed-bits w 16))
+
+(defun binformat (n &optional s)
+  (unless s
+    (setq s ""))
+  (let ((d (/ n 2))
+        (new-s (concat (number-to-string (mod n 2)) s)))
+    (if (= d 0)
+        new-s
+      (binformat d new-s))))
 
 ;; Memory
 
@@ -236,7 +256,7 @@
    ((= var 0)
     (ez-routine-stack-pop))
    ((< var 16)
-    (ez-get-local-var (- var 1)))
+    (ez-get-local-var var))
    (t
     (ez-get-global-var (- var 16)))))
 
@@ -245,7 +265,7 @@
    ((= var 0)
     (ez-routine-stack-push val))
    ((< var 16)
-    (ez-set-local-var (- var 1) val))
+    (ez-set-local-var var val))
    (t
     (ez-set-global-var (- var 16) val))))
 
@@ -253,7 +273,8 @@
   (ez-get-var (ez-read-pc-byte-and-inc)))
 
 (defun ez-execute-instr ()
-  (let ((opbyte (ez-read-pc-byte-and-inc))
+  (let ((instr-pc (ez-get-pc))
+        (opbyte (ez-read-pc-byte-and-inc))
         (optype)
         (opcode nil)
         (operands))
@@ -262,34 +283,41 @@
       (setq optype '2op
             opcode opbyte
             operands (list (ez-read-pc-byte-and-inc)
-                            (ez-read-pc-byte-and-inc))))
+                           (ez-read-pc-byte-and-inc))
+            operand-types '(b b)))
      ((<= #x20 opbyte #x3F)
       (setq optype '2op
             opcode (- opbyte #x20)
             operands (list (ez-read-pc-byte-and-inc)
-                           (ez-read-pc-var-and-inc))))
+                           (ez-read-pc-var-and-inc))
+            operand-types '(b w)))
      ((<= #x40 opbyte #x5F)
       (setq optype '2op
             opcode (- opbyte #x40)
             operands (list (ez-read-pc-var-and-inc)
-                           (ez-read-pc-byte-and-inc))))
+                           (ez-read-pc-byte-and-inc))
+            operand-types '(w b)))
      ((<= #x60 opbyte #x7F)
       (setq optype '2op
             opcode (- opbyte #x60)
             operands (list (ez-read-pc-var-and-inc)
-                           (ez-read-pc-var-and-inc))))
+                           (ez-read-pc-var-and-inc))
+            operand-types '(w w)))
      ((<= #x80 opbyte #x8F)
       (setq optype '1op
             opcode (- opbyte #x80)
-            operands (list (ez-read-pc-word-and-inc))))
+            operands (list (ez-read-pc-word-and-inc))
+            operand-types '(w)))
      ((<= #x90 opbyte #x9F)
       (setq optype '1op
             opcode (- opbyte #x90)
-            operands (list (ez-read-pc-byte-and-inc))))
+            operands (list (ez-read-pc-byte-and-inc))
+            operand-types '(b)))
      ((<= #xA0 opbyte #xAF)
       (setq optype '1op
             opcode (- opbyte #xa0)
-            operands (list (ez-read-pc-var-and-inc))))
+            operands (list (ez-read-pc-var-and-inc))
+            operand-types '(w)))
      ((<= #xB0 opbyte #xBF)
       (setq optype '0op
             opcode (- opbyte #xb0)))
@@ -297,16 +325,17 @@
       (error "Unsupported op" opbyte))
      ((<= #xE0 opbyte #xFF)
       (setq optype 'var
-            opcode (- opbyte #xe0)
-            operands (ez-read-var-operands-and-inc))))
+            opcode (- opbyte #xe0))
+      (let ((operands-and-types (ez-read-var-operands-and-inc)))
+        (setq operands (car operands-and-types)
+              operand-types (cdr operands-and-types)))))
     (let ((table-row (assoc (list optype opcode) ez-op-table)))
       (unless table-row
         (error "Unsupported op" optype opcode))
       (let ((mnemonic (elt table-row 1)))
-        (message "Optype:%s Opcode:%x Operands:%s"
-                 (symbol-name optype)
-                 opcode operands))
-      (apply (elt table-row 2) operands))))
+        (message "PC:%x Optype:%s Opcode:%x Mnemonic:%s Operands:%s"
+                 instr-pc optype opcode mnemonic operands))
+      (funcall (elt table-row 2) operands operand-types))))
 
 (defun ez-read-var-operands-and-inc ()
   (let* ((type-byte (ez-read-pc-byte-and-inc))
@@ -328,27 +357,158 @@
                                                     nil
                                                   (list type4)))))))))))))
          (operands nil))
-    (mapcar
-     (lambda (type)
-       (cond
-        ((= type 0) (ez-read-pc-word-and-inc))
-        ((= type 1) (ez-read-pc-byte-and-inc))
-        ((= type 2) (ez-read-pc-var-and-inc))))
-     types)))
+    (cons
+     (mapcar
+      (lambda (type)
+        (cond
+         ((= type 0) (ez-read-pc-word-and-inc))
+         ((= type 1) (ez-read-pc-byte-and-inc))
+         ((= type 2) (ez-read-pc-var-and-inc))))
+      types)
+     (mapcar
+      (lambda (type)
+        (if (= type 1)
+            'b
+          'w))
+      types))))
+
+;; Branches
+
+(defun ez-do-branch (branch)
+  (let* ((branch-byte (ez-read-pc-byte-and-inc))
+         (invert (= 0 (logand branch-byte #b10000000)))
+         (single-byte (= 1 (logand branch-byte #b01000000)))
+         (offset
+          (if single-byte
+              (logand branch-byte #b00111111)
+            (let ((pos (= (logand branch-byte #b00100000) 0))
+                  (val (+ (* 256 (logand branch-byte #b00011111))
+                          (ez-read-pc-byte-and-inc))))
+              (if pos
+                  val
+                (- val 8192))))))
+    (cond
+     ((= offset 0)
+      (ez-op-rfalse))
+     ((= offset 1)
+      (ez-op-rtrue))
+     (t
+      (ez-set-pc (+ (ez-get-pc) offset -2))))))
+
+;; Operations
 
 (defvar ez-op-table
-  '(((var #x0) call_fv ez-op-callf)))
+  '(((0op #x00) rtrue ez-op-rtrue)
+    ((0op #x01) rfalse ez-op-rfalse)
+    ((1op #x00) jz ez-op-jz)
+    ((1op #x0B) ret ez-op-ret)
+    ((1op #x0C) jump ez-op-jump)
+    ((2op #x0D) store ez-op-store)
+    ((1op #x0E) load ez-op-load)
+    ((var #x01) storew ez-op-storew)
+    ((2op #x01) je ez-op-je)
+    ((2op #x08) or ez-op-or)
+    ((2op #x09) and ez-op-and)
+    ((2op #x14) add ez-op-add)
+    ((2op #x15) sub ez-op-sub)
+    ((2op #x16) mul ez-op-mul)
+    ((2op #x17) div ez-op-div)
+    ((2op #x18) mod ez-op-mod)
+    ((var #x00) call_fv ez-op-callf)))
+
+(defun ez-op-ret (operands &optional operand-types)
+  (let ((retval (car operands)))
+    (ez-pop-call-stack-frame)
+    (ez-set-var (ez-read-pc-byte-and-inc) retval))
+  t)
+
+(defun ez-op-rtrue (&optional operands operand-types)
+  (ez-op-ret (list 1)))
+
+(defun ez-op-rfalse (&optional operands operand-types)
+  (ez-op-ret (list 0)))
+
+(defun ez-op-jz (operands operand-types)
+  (ez-do-branch (= (car operands) 0))
+  t)
+
+(defun ez-op-je (operands operand-types)
+  (ez-do-branch (memq (car operands) (cdr operands)))
+  t)
 
-(defun ez-op-callf (raddr &rest operands)
-  (let* ((r (* 2 raddr))
+(defun ez-op-jump (operands operand-types)
+  (let ((offset (if (eq (car operand-types) 'b)
+                    (ez-decode-signed-byte (car operands))
+                  (ez-decode-signed-word (car operands)))))
+    (ez-set-pc (+ (ez-get-pc) offset -2)))
+  t)
+
+(defun ez-op-store (operands operand-types)
+  (let ((var (car operands))
+        (a (cadr operands)))
+    (ez-set-var var a))
+  t)
+
+(defun ez-op-load (operands operand-types)
+  (let ((var (car operands)))
+    (ez-set-var (ez-read-pc-byte-and-inc) (ez-get-var var)))
+  t)
+
+(defun ez-op-storew (operands operand-types)
+  (let ((baddr (car operands))
+        (n (cadr operands))
+        (a (caddr operands)))
+    (ez-mem-set-word (+ baddr (* 2 n)) a))
+  t)
+
+(defun ez-op-and (operands operand-types)
+  (let ((a (car operands))
+        (b (cadr operands)))
+    (ez-set-var (ez-read-pc-byte-and-inc) (logand a b)))
+  t)
+
+(defun ez-op-or (operands operand-types)
+  (let ((a (car operands))
+        (b (cadr operands)))
+    (ez-set-var (ez-read-pc-byte-and-inc) (logior a b)))
+  t)
+
+(defun ez-op-add (operands operand-types)
+  (let ((a (car operands))
+        (b (cadr operands)))
+    (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ a b) #x10000)))
+  t)
+
+(defun ez-op-sub (operands operand-types)
+  (let ((a (car operands))
+        (b (cadr operands)))
+    (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ (- a b) #x10000) #x10000)))
+  t)
+
+(defun ez-op-mul (a b)
+  (let ((a (car operands))
+        (b (cadr operands)))
+    (ez-set-var (ez-read-pc-byte-and-inc) (mod (* a b) #x10000)))
+  t)
+
+(defun ez-op-div (a b)
+  (error "Not implemented"))
+
+(defun ez-op-mod (a b)
+  (error "Not implemented"))
+
+(defun ez-op-callf (operands operand-types)
+  (let* ((raddr (car operands))
+         (call-operands (cdr operands))
+         (r (* 2 raddr))
          (L (ez-mem-ref-byte r))
-         (n (length operands))
+         (n (length call-operands))
          (new-pc (+ r 1 (* L 2))))
     (ez-add-call-stack-frame new-pc)
     (dotimes (i L)
       (if (< i n)
-          (ez-set-local-var (+ i 1) (elt operands i))
-        (ez-set-local-var (+ i 1) (ez-mem-ref-byte (+ r 1 (* 2 i)))))))
+          (ez-set-local-var (+ i 1) (elt call-operands i))
+        (ez-set-local-var (+ i 1) (ez-mem-ref-word (+ r 1 (* 2 i)))))))
   t)
 
 ;; Main
@@ -367,33 +527,23 @@
 (setq ez-call-stack (list (ez-make-call-stack-frame ez-start-pc)))
 (ez-execute-instr)
 
-(binformat #x9b)
-"10 01 10 11"
+(binformat #x97)
+"10010111"
+
+
+ez-call-stack
+((28281 nil [33807 0 180 47872 0 0 0 0 0 0 0 0 ...] nil) (22022 nil [33807 65535 0 0 0 0 0 0 0 0 0 0 ...] nil) (20715 nil [0 0 0 0 0 0 0 0 0 0 0 0 ...] nil))
+
+((22049 nil [33807 0 180 47872 0 0 0 0 0 0 0 0 ...] nil) (22022 nil [33807 65535 0 0 0 0 0 0 0 0 0 0 ...] nil) (20715 nil [0 0 0 0 0 0 0 0 0 0 0 0 ...] nil))
+
 
-(* 2 #x2b07)
 
-"10011011"
 
-#b00101111
-(lsh #x2f)
 
-ez-call-stack
 
-(binformat #x2f)
-"10 11 11"
-(* 2 #x2b07)
 
 
-(ez-get-obj 1)
 
-(defun binformat (n &optional s)
-  (unless s
-    (setq s ""))
-  (let ((d (/ n 2))
-        (new-s (concat (number-to-string (mod n 2)) s)))
-    (if (= d 0)
-        new-s
-      (binformat d new-s))))